It really depends on what your goals are and where your cow herd is at now.
I am not a huge fan of Harland although I wouldn't be afraid of his birthweight. He will certainly work in the right situation. I would rather use the 3027 bull as the ones I have seen have had a little more thickness and doability on less frame than the Harlands. I have seen quite a few harlands that just dont have enough volume and thickness for their frame that I like to see. In addition his fat numbers are really really high, like in the fatest 1/2 percent in the breed. I tend to stay away from extremes like that. If you want to stay within the ABS lineup of bulls, and 3027 isn't enough performance for you look at the Ribeye bull or if you want alot of growth check into the Thor bull too, but he isn't as well proven yet.
Lots of options out there too if you want to work with private breeders whose bulls aren't in some fancy semen catalog that work in the real world.
Brian